Diagnosing Bipolar Disorder
Bipolar disorder is difficult to diagnose. Because bipolar is a mood disorder, tests such as blood tests, brain scans, x-rays and personality tests will not reveal the existence of the illness. Making a diagnosis currently requires recognising a constellation of symptoms, as well as 'ruling out' other possible explanations for the observed disturbance such as depression, physical illness or substance abuse. It has been suggested that it can often take an average of five years from the onset of symptoms to reach the correct diagnosis. (Evans, 2000) The main job of the psychiatrist is to eliminate all other possibilities before making a definitive diagnosis of bipolar disorder. Bipolar disorder often first presents with depressive episodes, but it is not until a person suffers from a characteristic manic episode that the diagnosis can be conclusively made.
There are two major systems currently used for the diagnosis of bipolar disorder, the Diagnostic and Statistical Manual of Mental Disorders and the International Classification of Disease. These classifications have the effect of improving the reliability of diagnosis but the validity of diagnosis still remains a problem.
Diagnostic & Statistical Manual of Mental Disorders (DSM-IV) Criteria for Bipolar Disorder:
People with bipolar disorder may also experience psychosis in the manic and/or depressed phase. A variety of types of bipolar disorder exist and it is not one single illness. According to the Diagnostic and Statistical Manual of Mental Disorders (DSM, IV), the following are the distinct types:
Types of Bipolar Disorder:
Bipolar 1 disorder: characterised by one of more major manic or mixed episodes, usually accompanied by major depressive episodes.
Bipolar 2 disorder: characterised by one of major depressive episodes accompanied by at least one hypomanic episode.
Cyclothymic disorder: characterised by at least two years of numerous periods of hypomanic symptoms (that do not meet the criteria for a manic episode) and numerous periods of depressive symptoms (that do not meet the criteria for a major depressive episode).
Bipolar disorder (unspecified): where bipolar features exist but they do not meet any of the criteria for any of the specific diagnoses above. DSM IV further divides these distinct types into many subcategories.
These are the definitions of Bipolar Disorder I and Bipolar Disorder II:
Bipolar Disorder I
“The essential feature of Bipolar I Disorder is a clinical course that is characterized by the occurrence of one or more Manic Episodes or Mixed Episodes. Often individuals have also had one or more Major Depressive Episodes. Episodes of Substance-Induced Mood Disorder (due to the direct effects of a medication, or other somatic treatments for depression, a drug of abuse, or toxin exposure) or of Mood Disorder Due to a General Medical Condition do not count toward a diagnosis of Bipolar I Disorder.” (DSM-IV, p. 350)
Bipolar Disorder II
“The essential feature of Bipolar II Disorder is a clinical course that is characterized by the occurrence of one or more Major Depressive Episodes accompanied by at least one Hypomanic Episode. Hypomanic Episodes should not be confused with the several days of euthymia that may follow remission of a Major Depressive Episode. Episodes of Substance- Induced Mood Disorder (due to the direct effects of a medication, or other somatic treatments for depression, a drug of abuse, or toxin exposure) or of Mood Disorder Due to a General Medical Condition do not count toward a diagnosis of Bipolar I Disorder.” (DSM-IV, p. 359)